Optics and Photonics Society of Iran

Photonic crystal waveguides are one of the important key components in an all-optical integrated circuit. They localize light inside the guiding region for transmission of optical energy. A major challenge to design an efficiency-improved photonic crystal waveguide is the issue of loss. In this paper, the effect of spectral dispersion on the loss reduction is examined through Lithium Tantalate as a strong dispersive dielectric material. The waveguide structure consists of the square lattice of Lithium Tantalate cylinders in air matrix. It has been shown that energy loss related to some waveguide Eigen modes are appreciably mitigated using dispersive dielectric cylinders in the structure compared to that of corresponding structure made of non-dispersive dielectric cylinders. The method used for extracting the corresponding projected band structure and the attenuation coefficient of the modal fields is two-dimensional finite-difference time-domain method for dispersive structures